COMPArison of Multi-Point Pacing and ConvenTional Cardiac Resynchronization Therapy Through Noninvasive Hemodynamics Measurement: Short- and Long-Term Results of the COMPACT-MPP Study

Invasive hemodynamic studies have shown improved left ventricular (LV) performances when cardiac resynchronization therapy/defibrillator is delivered through multipoint pacing (MPP). Nowadays, strategies have become available that allow studying the same hemodynamic parameters at a noninvasive level. The aim of the present study was to evaluate the clinical implication of using a patient-tailored approach for cardiac resynchronization therapy programming based on noninvasively assessed LV hemodynamics to identify the best biventricular pacing modality between standard single-site pacing (STD) and MPP for each patient. Therefore, 51 patients with heart failure (age 69 ± 9 years, 35 men, 27% ischemic etiology) implanted with cardiac resynchronization therapy/defibrillator underwent noninvasive LV function assessment through photoplethysmography before hospital discharge for addressing dP/dt and stroke volume in both pacing modalities (STD and MPP). The modality that performed better in terms of hemodynamic improvement was permanently programmed. Global longitudinal strain (GLS) was also assessed, and repeated at 3 months. Compared with intrinsic rhythm (928 ± 486 mm Hg/s), dP/dtmax showed a trend to increase in both biventricular pacing modes (1,000 ± 577 mm Hg/s in STD, 1,036 ± 530 mm Hg/s in MPP, p = NS). MPP was associated with a wider hemodynamic improvement than was STD and was the modality of choice in 34 of 51 patients (67%). GLS at predischarge did not differ between groups (-10.3 ± 3.8% vs -10.2 ± 3.5%), but significant improvement of ejection fraction at 1 month (34.4 ± 5.3%, p <0.001) and of GLS at 3 months (-12.9 ± 2.9%, p <0.005) was observed across the entire cohort. At 3 months, 77% of patients were classified as responders. Interestingly, long-term (3 years) follow-up unveiled a reduction in all-cause mortality in the MPP group compared with the STD group. In conclusion, cardiac resynchronization therapy programming guided by acute noninvasive hemodynamics favored MPP modality and caused short-term LV positive remodeling and improved long-term outcomes. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT04299360.

CDK5R1, GSE1, HSPG2 and WDFY3 as indirect epigenetic-sensitive genes in atrial fibrillation

BACKGROUND

Although mounting evidence supports that aberrant DNA methylation occurs in the hearts of patients with atrial fibrillation (AF), noninvasive epigenetic characterization of AF has not yet been defined.

METHODS

We investigated DNA methylome changes in peripheral blood CD4+ T cells isolated from 10 patients with AF relative to 11 healthy subjects (HS) who were enrolled in the DIANA clinical trial (NCT04371809) via reduced-representation bisulfite sequencing (RRBS).

RESULTS

An atrial-specific PPI network revealed 18 hub differentially methylated genes (DMGs), wherein ROC curve analysis revealed reasonable diagnostic performance of DNA methylation levels found within CDK5R1 (AUC = 0.76; p = 0.049), HSPG2 (AUC = 0.77; p = 0.038), WDFY3 (AUC = 0.78; p = 0.029), USP49 (AUC = 0.76; p = 0.049), GSE1 (AUC = 0.76; p = 0.049), AIFM1 (AUC = 0.76; p = 0.041), CDK5RAP2 (AUC = 0.81; p = 0.017), COL4A1 (AUC = 0.86; p < 0.001), SEPT8 (AUC = 0.90; p < 0.001), PFDN1 (AUC = 0.90; p < 0.01) and ACOT7 (AUC = 0.78; p = 0.032). Transcriptional profiling of the hub DMGs provided a significant overexpression of PSDM6 (p = 0.004), TFRC (p = 0.01), CDK5R1 (p < 0.001), HSPG2 (p = 0.01), WDFY3 (p < 0.001), USP49 (p = 0.004) and GSE1 (p = 0.021) in AF patients vs HS.

CONCLUSIONS

CDK5R1, GSE1, HSPG2 and WDFY3 resulted the best discriminatory genes both at methylation and gene expression level. Our results provide several candidate diagnostic biomarkers with the potential to advance precision medicine in AF.

Endothelial Dysfunction Drives CRTd Outcome at 1-Year Follow-Up: A Novel Role as Biomarker for miR-130a-5p

Endothelial dysfunction (ED) causes worse prognoses in heart failure (HF) patients treated with cardiac resynchronization therapy (CRTd). ED triggers the downregulation of microRNA-130 (miR-130a-5p), which targets endothelin-1 (ET-1). Thus, we evaluated ED and the response to CRTd by assessing miR-130a-5p and ET-1 serum levels. We designed a prospective multi-center study with a 1-year follow-up to evaluate ED, ET-1, and miR-130a-5p in CRTd patients with ED (ED-CRTd) vs. patients without ED (NED-CRTd). Clinical outcomes were CRTd response, HF hospitalization, cardiac death, and all-cause death. At 1-year follow-up, NED-CRTd (n = 541) vs. ED-CRTd (n = 326) patients showed better clinical statuses, lower serum values of B type natriuretic peptide (BNP: 266.25 ± 10.8 vs. 297.43 ± 16.22 pg/mL; p < 0.05) and ET-1 (4.57 ± 0.17 vs. 5.41 ± 0.24 pmol/L; p < 0.05), and higher values of miR-130a-5p (0.51 ± 0.029 vs. 0.41 ± 0.034 A.U; p < 0.05). Compared with NED-CRTd patients, ED-CRTd patients were less likely to be CRTd responders (189 (58%) vs. 380 (70.2%); p < 0.05) and had higher rates of HF hospitalization (115 (35.3%) vs. 154 (28.5%); p < 0.05) and cardiac deaths (30 (9.2%) vs. 21 (3.9%); p < 0.05). Higher miR-130a-5p levels (HR 1.490, CI 95% [1.014−2.188]) significantly predicted CRTd response; the presence of hypertension (HR 0.818, CI 95% [0.669−0.999]), and displaying higher levels of ET-1 (HR 0.859, CI 98% [0.839−0.979]), lymphocytes (HR 0.820, CI 95% [0.758−0.987]), LVEF (HR 0.876, CI 95% [0.760−0.992]), and ED (HR 0.751, CI 95% [0.624−0.905]) predicted CRTd non-response. Higher serum miR-130a-5p levels (HR 0.332, CI 95% [0.347−0.804]) and use of ARNI (HR 0.319, CI 95% [0.310−0.572]) predicted lower risk of HF hospitalization, whereas hypertension (HR 1.818, CI 95% [1.720−2.907]), higher BNP levels (HR 1.210, CI 95% [1.000−1.401]), and presence of ED (HR 1.905, CI 95% [1.238−2.241]) predicted a higher risk of HF hospitalization. Hence, serum miR-130a-5p could identify different stages of ED and independently predict CRTd response, therefore representing a novel prognostic HF biomarker.

Shock-Augmented Ignition Approach to Laser Inertial Fusion

Shock ignition enables high gain at low implosion velocity, reducing ablative Rayleigh-Taylor instability growth, which can degrade conventional direct drive. With this method, driving a strong shock requires high laser power and intensity, resulting in inefficiencies in the drive and the generation of hot electrons that can preheat the fuel. A new "shock-augmented ignition" pulse shape is described that, by preconditioning the ablation plasma before launching a strong shock, enables the shock ignition of thermonuclear fuel, but importantly, with substantially reduced laser power and intensity requirements. The reduced intensity requirement with respect to shock ignition limits laser-plasma instabilities, such as stimulated Raman and Brillouin scatter, reducing the risk of hot-electron preheat and restoring the laser coupling advantages of conventional direct drive. Simulations indicate that, due to the reduced power requirements, high gain (∼100) ignition of large-scale direct drive implosions (outer radius ∼1750  μm, deuterium-tritium ice thickness ∼165  μm) may be possible within the power and energy limits of existing facilities such as the National Ignition Facility. Moreover, this concept extends to indirect drive implosions, which exhibit substantial yield increases at reduced implosion velocity. Shock-augmented ignition expands the viable design space of laser inertial fusion.

De novo DNA methylation induced by circulating extracellular vesicles from acute coronary syndrome patients

BACKGROUND AND AIMS

DNA methylation is associated with gene silencing, but its clinical role in cardiovascular diseases (CVDs) remains to be elucidated. We hypothesized that extracellular vesicles (EVs) may carry epigenetic changes, showing themselves as a potentially valuable non-invasive diagnostic liquid biopsy. We isolated and characterized circulating EVs of acute coronary syndrome (ACS) patients and assessed their role on DNA methylation in epigenetic modifications.

METHODS

EVs were recovered from plasma of 19 ACS patients and 50 healthy subjects (HS). Flow cytometry, qRT-PCR, and Western blot (WB) were performed to evaluate both intra-vesicular and intra-cellular signals. ShinyGO, PANTHER, and STRING tools were used to perform GO and PPI network analyses.

RESULTS

ACS-derived EVs showed increased levels of DNA methyltransferases (DNMTs) (p<0.001) and Ten-eleven translocation (TET) genes reduction. Specifically, de novo methylation transcripts, as DNMT3A and DNMT3B, were significantly increased in plasma ACS-EVs. DNA methylation analysis on PBMCs from healthy donors treated with HS- and ACS-derived EVs showed an important role of DNMTs carried by EVs. PPI network analysis evidenced that ACS-EVs induced changes in PBMC methylome. In the most enriched subnetwork, the hub gene SRC was connected to NOTCH1, FOXO3, CDC42, IKBKG, RXRA, DGKG, BAIAP2 genes that were showed to have many molecular effects on various cell types into onset of several CVDs. Modulation in gene expression after ACS-EVs treatment was confirmed for SRC, NOTCH1, FOXO3, RXRA, DGKG and BAIAP2 (p<0.05).

CONCLUSIONS

Our data showed an important role for ACS-derived EVs in gene expression modulation through de novo DNA methylation signals, and modulating signalling pathways in target cells.

ABCA1, TCF7, NFATC1, PRKCZ and PDGFA DNA methylation as potential epigenetic-sensitive targets in acute coronary syndrome via network analysis

Background

Acute coronary syndrome (ACS) is the most severe clinical manifestation of coronary heart disease and the leading cause of death worldwide.

Purpose

To perform an epigenome-wide analysis in circulating CD4+ and CD8+ T cells of ACS patients and healthy subjects (HS) enrolled in the DIANA clinical trial (NCT04371809) in order to identify differentially methylated genes (DMGs).

Methods

Genomic DNA was extracted from CD4+ and CD8+ T cells of all subjects and sequenced by the reduced representation bisulfite sequencing (RRBS) platform. Functional pathway analysis was performed and significant DMGs were selected for gene expression validation by qRT-PCR in ACS patients and HS. GeneMANIA was used to built a prediction gene network. Correlation analyses between molecular data and clinical variables were performed.

Results

In CD4+ T cells we identified 61 differentially methylated regions (DMRs) associated to 57 annotated genes of which 53% (n=32) were hyper- and 47% (n=29) were hypo-methylated in ACS patients vs HS. In CD8+ T cells we identified 613 DMRs associated to 569 annotated genes of which 28% (n=173) were hyper- and 72% (n=440) were hypo-methylated between two groups. In both cell type of ACS patients, 175 DMRs were associated to 157 annotated genes of which 41% (n=72) were hyper- and 59% (n=103) were hypo-methylated. From functional analysis, we selected the top 5 DMGs in the prevalent pathways with the highest differential of methylation values. Specifically, we considered 6 hub genes: NFATC1, TCF7, PDGFA, PRKCB, PRKCZ and ABCA1 and determined their respective expression levels by q-RT-PCR. We found a significant up-regulation of the selected genes in ACS patients vs HS (P&lt;0.001 for all comparisons). Correlation analysis showed both common and cell specific correlation patterns. In CD4+ T cells, PDGFA promoter methylation was negatively correlated with CK-MB concentrations (r=−0.79, P=0.018). ABCA1, TCF7, PDGFA and PRKCZ gene expression was positively associated to CK-MB concentrations (r=0.75, P=0.03; r=0.760, P=0.029; r=0.72, P=0.044; r=0.74, P=0.035, respectively).

Conlusions

This study is the first single-base resolution map of DNA methylome by RRBS in CD4+ and CD8+ T cells, providing specific methylation signatures that could help to clarify the role of aberrant methylation in ACS pathogenesis, and provide the basis for the search of novel epigenetic-sensitive biomarkers in the prevention and early diagnosis of this pathology.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Italian Ministry of Health;Italian Ministry of Research and University

ABCA1, TCF7, NFATC1, PRKCZ, and PDGFA DNA methylation as potential epigenetic-sensitive targets in acute coronary syndrome via network analysis

Acute coronary syndrome (ACS) is the most severe clinical manifestation of coronary heart disease.We performed an epigenome-wide analysis of circulating CD4⁺ and CD8⁺ T cells isolated from ACS patients and healthy subjects (HS), enrolled in the DIANA clinical trial, by reduced-representation bisulphite sequencing (RRBS). In CD4⁺ T cells, we identified 61 differentially methylated regions (DMRs) associated with 57 annotated genes (53% hyper- and 47% hypo-methylated) by comparing ACS patients vs HS. In CD8⁺ T cells, we identified 613 DMRs associated with 569 annotated genes (28% hyper- and 72% hypo-methylated) in ACS patients as compared to HS. In CD4⁺ vs CD8⁺ T cells of ACS patients we identified 175 statistically significant DMRs associated with 157 annotated genes (41% hyper- and 59% hypo-methylated). From pathway analyses, we selected six differentially methylated hub genes (NFATC1, TCF7, PDGFA, PRKCB, PRKCZ, ABCA1) and assessed their expression levels by q-RT-PCR. We found an up-regulation of selected genes in ACS patients vs HS (P < 0.001). ABCA1, TCF7, PDGFA, and PRKCZ gene expression was positively associated with CK-MB serum concentrations (r = 0.75, P = 0.03; r = 0.760, P = 0.029; r = 0.72, P = 0.044; r = 0.74, P = 0.035, respectively).This pilot study is the first single-base resolution map of DNA methylome by RRBS in CD4⁺ and CD8⁺ T cells and provides specific methylation signatures to clarify the role of aberrant methylation in ACS pathogenesis, thus supporting future research for novel epigenetic-sensitive biomarkers in the prevention and early diagnosis of this pathology.

High-responsivity graphene photodetectors integrated on silicon microring resonators

Graphene integrated photonics provides several advantages over conventional Si photonics. Single layer graphene (SLG) enables fast, broadband, and energy-efficient electro-optic modulators, optical switches and photodetectors (GPDs), and is compatible with any optical waveguide. The last major barrier to SLG-based optical receivers lies in the current GPDs' low responsivity when compared to conventional PDs. Here we overcome this by integrating a photo-thermoelectric GPD with a Si microring resonator. Under critical coupling, we achieve >90% light absorption in a ~6 μm SLG channel along a Si waveguide. Cavity-enhanced light-matter interactions cause carriers in SLG to reach ~400 K for an input power ~0.6 mW, resulting in a voltage responsivity ~90 V/W, with a receiver sensitivity enabling our GPDs to operate at a 10-9 bit-error rate, on par with mature semiconductor technology, but with a natural generation of a voltage, rather than a current, thus removing the need for transimpedance amplification, with a reduction of energy-per-bit, cost, and foot-print.

Cardiac implantable electronic devices replacements in patients followed by remote monitoring during COVID-19 lockdown

Aims 

Following coronavirus disease (COVID-19) outbreak, the Italian government adopted strict rules of lockdown and social distancing. The aim of our study was to assess the admission rate for cardiac implantable electronic devices (CIEDs) replacement procedures in Campania, the 3rd-most-populous region of Italy, during COVID-19 lockdown.

Methods and results 

Data were sourced from 16 referral hospitals in Campania from 10 March to 4 May 2020 (lockdown period) and during the same period in 2019. We retrospectively evaluated consecutive patients hospitalized for CIEDs replacement procedures during the two observational periods. The number and type of CIEDs replacement procedures among patients followed by remote monitoring (RM), the admission rate, and the type of hospital admission between the two observational periods were compared. In total, 270 consecutive patients were hospitalized for CIEDs replacement procedures over the two observation periods. Overall CIEDs replacement procedures showed a reduction rate of 41.2% during COVID-19 lockdown. Patients were equally distributed for sex (P = 0.581), and both age [median 76 years (IQR: 68–83) vs. 79 years (IQR: 68–83); P = 0.497]. Cardiac implantable electronic devices replacement procedures in patients followed by RM significantly increased (IR: +211%; P < 0.001), mainly driven by the remarkable increase rate trend of both PM (IR: +475%; P < 0.001) and implantable cardiac defibrillator replacement procedures (IR: +67%, P = 0.01), during COVID-19 lockdown compared with 2019 timeframe.

Conclusions 

We showed a significant increase trend rate of replacement procedures among CIEDs patients followed by RM, suggesting the hypothesis of its increased use to closely monitoring and to optimize the hospital admission time during COVID-19 lockdown.

Cardiac resynchronization therapy and its effects in patients with type 2 DIAbetes mellitus OPTimized in automatic vs. echo guided approach. Data from the DIA-OPTA investigators

Objectives

To evaluate the effects of cardiac resynchronization therapy (CRTd) in patients with type 2 diabetes mellitus (T2DM) optimized via automatic vs. echocardiography-guided approach.

Background

The suboptimal atrio-ventricular (AV) and inter-ventricular (VV) delays optimization reduces CRTd response. Therefore, we hypothesized that automatic CRTd optimization might improve clinical outcomes in T2DM patients.

Methods

We designed a prospective, multicenter study to recruit, from October 2016 to June 2019, 191 consecutive failing heart patients with T2DM, and candidate to receive a CRTd. Study outcomes were CRTd responders rate, hospitalizations for heart failure (HF) worsening, cardiac deaths and all cause of deaths in T2DM patients treated with CRTd and randomly optimized via automatic (n 93) vs. echocardiography-guided (n 98) approach at 12 months of follow-up.

Results

We had a significant difference in the rate of CRTd responders (68 (73.1%) vs. 58 (59.2%), p 0.038), and hospitalizations for HF worsening (12 (16.1%) vs. 22 (22.4%), p 0.030) in automatic vs. echocardiography-guided group of patients. At multivariate Cox regression analysis, the automatic guided approach (3.636 [1.271–10.399], CI 95%, p 0.016) and baseline highest values of atrium pressure (automatic SonR values, 2.863 [1.537–6.231], CI 95%, p 0.006) predicted rate of CRTd responders. In automatic group, we had significant difference in SonR values comparing the rate of CRTd responders vs. non responders (1.24 ± 0.72 g vs. 0.58 ± 0.46 g (follow-up), p 0.001), the rate of hospitalizations for HF worsening events (0.48 ± 0.29 g vs. 1.18 ± 0.43 g, p 0.001), and the rate of cardiac deaths ( 1.13 ± 0.72 g vs. 0.65 ± 0.69 g, p 0.047).

Conclusions

Automatic optimization increased CRTd responders rate, and reduced hospitalizations for HF worsening. Intriguingly, automatic CRTd and highest baseline values of SonR could be predictive of CRTd responders. Notably, there was a significant difference in SonR values for CRTd responders vs. non responders, and about hospitalizations for HF worsening and cardiac deaths.

Clinical trial ClinicalTrials.gov Identifier NCT04547244.

Arrhythmogenic syncope leading to cardiac rhythm management procedures during COVID-19 lockdown

Introduction: Following the coronavirus disease (COVID-19) outbreak, the Italian government adopted strict rules of lockdown and social distancing. The aim of our study was to assess admission rate for syncope leading to cardiac rhythm management (CRM) procedures in Campania, the third-most-populous region of Italy, during COVID-19 lockdown. Methods: Data were sourced from 14 referral hospitals in Campania from 10^th March to 4 May 2020 (lockdown period) and during the same period in 2019. Among consecutive patients hospitalized for CRM procedures during the two observational periods, we retrospectively evaluated those admitted for arrhythmogenic syncope. Admission rate and the type of hospital admission between the two observational periods were compared. Results: Among 951 consecutive patients hospitalized for CRM procedures, 204 were admitted for arrhythmogenic syncope leading to CRM procedures. A significant increase in admission was shown in 2020 compared to 2019 (26.4% vs. 18.3%; P = 0.003). Moreover, regarding the type of admission to hospitals, attendance at the emergency department (ED) significantly increased (83.5% vs. 56.1%; P < 0.001); conversely, a significant decrease in urgent unplanned hospitalizations (6.2% vs. 35.5%; P < 0.001) was observed during COVID-19 lockdown. Conclusions: The hospitalization for arrhythmogenic syncope leading to CRM procedures increased during COVID-19 lockdown.

Integrated analysis of DNA methylation profile of HLA-G gene and imaging in coronary heart disease: Pilot study

Aims

Immune endothelial inflammation, underlying coronary heart disease (CHD) related phenotypes, could provide new insight into the pathobiology of the disease. We investigated DNA methylation level of the unique CpG island of HLA-G gene in CHD patients and evaluated the correlation with cardiac computed tomography angiography (CCTA) features.

Methods

Thirty-two patients that underwent CCTA for suspected CHD were enrolled for this study. Obstructive CHD group included fourteen patients, in which there was a stenosis greater than or equal to 50% in one or more of the major coronary arteries detected; whereas subjects with Calcium (Ca) Score = 0, uninjured coronaries and with no obstructive CHD (no critical stenosis, NCS) were considered as control subjects (n = 18). For both groups, DNA methylation profile of the whole 5’UTR-CpG island of HLA-G was measured. The plasma soluble HLA-G (sHLA-G) levels were detected in all subjects by specific ELISA assay. Statistical analysis was performed using R software.

Results

For the first time, our study reported that 1) a significant hypomethylation characterized three specific fragments (B, C and F) of the 5’UTR-CpG island (p = 0.05) of HLA-G gene in CHD patients compared to control group; 2) the hypomethylation level of one specific fragment of 161bp (+616/+777) positively correlated with coronary Ca score, a relevant parameter of CCTA (p<0.05) between two groups evaluated and was predictive for disease severity.

Conclusions

Reduced levels of circulating HLA-G molecules could derive from epigenetic marks. Epigenetics phenomena induce hypomethylation of specific regions into 5'UTR-CpG island of HLA-G gene in CHD patients with obstructive non critical stenosis vs coronary stenosis individuals.

Unexpectedly Large Electron Correlation Measured in Auger Spectra of Ferromagnetic Iron Thin Films: Orbital-Selected Coulomb and Exchange Contributions

A set of electron-correlation energies as large as 10 eV have been measured for a magnetic 2 ML Fe film deposited on Ag(001). By exploiting the spin selectivity in angle-resolved Auger-photoelectron coincidence spectroscopy and the Cini-Sawatzky theory, the core-valence-valence Auger spectrum of a spin-polarized system have been resolved: correlation energies have been determined for each individual combination of the two holes created in the four subbands involved in the decay: majority and minority spin, as well as e_{g} and t_{2g}. The energy difference between final states with parallel and antiparallel spin of the two emitted electrons is ascribed to the spin-flip energy for the final ion state, thus disentangling the contributions of Coulomb and exchange interactions.

P167 The burden of post-actinic heart disease: a case of severe valvular and coronary artery disease in a cancer survivor

Background

A 47-year old female complaining of exertional dyspnoea (NYHA class III) was admitted at our Cardiology department. She had a history of nodular sclerosis Hodgkin lymphoma (HL), treated with chemo- and radiotherapy, and complicated by post-actinic pneumopathy and cardiopathy. At the age of 39, she had undergone coronary artery bypass grafting with left internal mammal artery (LIMA) to left anterior descendent artery and saphenous vein to obtuse marginal branch, and aortic valve replacement with a mechanical prosthesis due to severe aortic stenosis. Some years later, she had undergone percutaneous stenting of the left main (LM) due to occlusion of the LIMA bypass graft.

At admission, the patient was hemodynamically stable, with signs of right-sided congestive heart failure. Both 2D and 3D transthoracic echocardiogram (TTE) showed preserved biventricular function, normal function of the aortic prosthesis, and diffuse calcification of the whole mitral valve apparatus, involving the leaflets, the annulus, the tendinous chords and the anterolateral papillary muscle (Figure Panels A-B), causing severe mitral stenosis (mean gradient 10 mmHg, 3D planimetric area 0.9 cm2, Wilkins score 12) and moderate organic insufficiency (Panel C). The tricuspid valve was also affected, with thickened, hypomobile leaflets, causing mild stenosis (mean gradient 4 mmHg, 3D planimetric area 3.8 cm2) and severe insufficiency (Panel D). Transesophageal echocardiogram (TOE) couldn"t be performed because of actinic oesophagitis. Percutaneous valvuloplasty was contraindicated due to moderate mitral insufficiency, high Wilkins score and a huge amount of calcium affecting the whole valve apparatus but sparing the commissures.

The patient was scheduled to PCI on the LM due to intrastent restenosis, but died during the procedure as a consequence of an intrastent massive thrombosis leading to cardiac arrest.

Learning points

Hodgkin lymphoma survivors are at increased cardiovascular and intraoperative risk. Old radiotherapy protocols for HL may cause severe post-actinic valvular and coronary disease. Post-actinic valvular heart disease often affects aortic and mitral valve more than a decade after irradiation, and may manifest as stenosis, insufficiency or both. Organic regurgitation and stenosis of tricuspid valve are uncommon, but may also occur and lead to worse patient outcome. Despite TOE may bring additional valuable informations in challenging cases, the coexistence of oesophageal sequelae from post-actinic oesophagitis may limit its applicability. TTE is the first line and often the only diagnostic tool available for identifying the characteristic valvular lesions in cancer survivors exposed to radiotherapy. 3D TTE may be particularly useful to identify subtle signs of primary involvement of tricuspid apparatus and quantify the anatomical area of a stenotic tricuspid valve, when severe regurgitation coexists and transvalvular gradients may be unreliable.

Abstract P167 Figure

P190 Chest pain and syncope in Turner"s syndrome: going beyond the obvious to not miss the critical diagnosis. Role of multimodality imaging approach

Learning points

Chest pain and syncope are challenging symptoms in pts presenting in ED. AV pathology and aortic dissection should be always suspected and ruled out. TS is associated with multiple congenital cardiovascular abnormalities and is the most common established cause of aortic dissection in young women. 30% of Turner’s pts have congenitally AV abnormalities, and dilation of the ascending aorta is frequently associated. However, unicuspid AV is a very rare anomaly, usually stenotic at birth and requiring replacement. The presence of pericardial effusion in a pt with chest pain and syncope should raise the suspicion of aortic dissection, even if those symptoms usually accompany severe aortic stenosis. Even if CT is the gold standard imaging technique to rule out aortic dissection, the accuracy of a test is critically related to the image quality. When the suspicion of dissection is high and the reliability of the reference test is low, it’s reasonable to perform a different test to rule out the pathology. Aortography and TOE were pivotal to identify the limited dissection of the ascending aorta.

Abstract P190 Figure.

Cardiac resynchronization therapy with a defibrillator (CRTd) in failing heart patients with type 2 diabetes mellitus and treated by glucagon-like peptide 1 receptor agonists (GLP-1 RA) therapy vs. conventional hypoglycemic drugs: arrhythmic burden, hospitalizations for heart failure, and CRTd responders rate

Objectives

To evaluate clinical outcomes in patients with diabetes, treated by cardiac resynchronization therapy with a defibrillator (CRT-d), and glucagon-like peptide 1 receptor agonists (GLP-1 RA) in addition to conventional hypoglycemic therapy vs. CRTd patients under conventional hypoglycemic drugs.

Background

Patients with diabetes treated by CRTd experienced an amelioration of functional New York Association Heart class, reduction of hospital admissions, and mortality, in a percentage about 60%. However, about 40% of CRTd patients with diabetes experience a worse prognosis.

Materials and methods

We investigated the 12-months prognosis of CRTd patients with diabetes, previously treated with hypoglycemic drugs therapy (n 271) vs. a matched cohort of CRTd patients with diabetes treated with GLP-1 RA in addition to conventional hypoglycemic therapy (n 288).

Results

At follow up CRTd patients with diabetes treated by GLP-1 RA therapy vs. CRTd patients with diabetes that did not receive GLP-1 RA therapy, experienced a significant reduction of NYHA class (p value < 0.05), associated to higher values of 6 min walking test (p value < 0.05), and higher rate of CRTd responders (p value < 0.05). GLP-1 RA patients vs. controls at follow up end experienced lower AF events (p value < 0.05), lower VT events (p value < 0.05), lower rate of hospitalization for heart failure worsening (p value < 0.05), and higher rate of CRTd responders (p value < 0.05). To date, GLP-1 RA therapy may predict a reduction of AF events (HR 0.603, CI [0.411–0.884]), VT events (HR 0.964, CI [0.963–0.992]), and hospitalization for heart failure worsening (HR 0.119, CI [0.028–0.508]), and a higher CRT responders rate (HR 3.707, CI [1.226–14.570]).

Conclusions

GLP-1 RA drugs in addition to conventional hypoglycemic therapy may significantly reduce systemic inflammation and circulating BNP levels in CRTd patients with diabetes, leading to a significant improvement of LVEF and of the 6 min walking test, and to a reduction of the arrhythmic burden. Consequently, GLP-1 RA drugs in addition to conventional hypoglycemic therapy may reduce hospital admissions for heart failure worsening, by increasing CRTd responders rate.

Trial registration NCT03282136. Registered 9 December 2017 “retrospectively registered”

III-V-on-silicon integrated micro - spectrometer for the 3 μm wavelength range

A compact (1.2 mm²) fully integrated mid-IR spectrometer operating in the 3 μm wavelength range is presented. To our knowledge this is the longest wavelength integrated spectrometer operating in the important wavelength window for spectroscopy of organic compounds. The spectrometer is based on a silicon-on-insulator arrayed waveguide grating filter. An array of InAs_0.91Sb_0.09 p-i-n photodiodes is heterogeneously integrated on the spectrometers output grating couplers using adhesive bonding. The spectrometer insertion loss is less than 3 dB and the waveguide-referred responsivity of the integrated photodiodes at room temperature is 0.3 A/W.

Evaluation of synergistic effects of resynchronization therapy and a β-blocker up-titration strategy based on a predefined patient-management program: the RESTORE study

Prior studies have suggested that a substantial number of eligible heart failure (HF) patients fail to receive β-blocker therapy, or receive it at a suboptimal dose. The aim of this study is to assess the benefit of a predefined management program designed for β-blocker up-titration, evaluating the synergistic effect of cardiac resynchronization therapy (CRT) and β-blockers in a HF population. The Resynchronization Therapy and β-Blocker Titration (RESTORE) study is a prospective, case-control, multicenter cohort study designed to test the hypothesis that a β-blocker up-titration strategy based on a predefined management program maximizes the beneficial effect of CRT, increasing the number of patients reaching the target dose of β-blockers and improving their clinical outcome. All study patients receive an implantable defibrillator for CRT delivery in accordance with current guidelines. Enrollments started in December 2011 and are scheduled to end in December 2014. Approximately 250 consecutive patients will be prospectively enrolled in 6 Italian centers and followed up for 24 months after implantation. The primary endpoint is to demonstrate that CRT may allow titration of β-blockers until the optimal dose, or at least to the effective dose, in patients with HF. This study might provide important information about the benefit of a predefined management program for β-blocker up-titration in patients receiving CRT. Moreover, assessment of health-care utilization and the consumption of resources will allow estimating the potential utility of remote monitoring by means of an automated telemedicine system in facilitating the titration of β-blockers in comparison with a standard in-hospital approach.

Silicon-on-insulator shortwave infrared wavelength meter with integrated photodiodes for on-chip laser monitoring

This paper demonstrates a very compact wavelength meter for on-chip laser monitoring in the shortwave infrared wavelength range based on an optimized arrayed waveguide grating (AWG) filter with an integrated photodiode array. The AWG response is designed to obtain large nearest neighbor crosstalk (i.e. large overlap) between output channels, which allows accurately measuring the wavelength of a laser under test using the centroid detection technique. The passive AWG is fabricated on a 220 nm silicon-on-insulator (SOI) platform and is combined with GaInAsSb-based photodiodes. The photodiodes are heterogeneously integrated on the output grating couplers of the AWG using DVS-BCB adhesive bonding. The complete device with AWG and detectors has a footprint of only 2 mm(2) while the measured accuracy and resolution of the detected wavelength is better than 20pm.

Combined effects of PI3K and SRC kinase inhibitors with imatinib on intracellular calcium levels, autophagy, and apoptosis in CML-PBL cells

Imatinib induces a complete cytogenetic regression in a large percentage of patients affected by chronic myeloid leukemia (CML) until mutations in the kinase domain of BCR-ABL appear. Alternative strategies for CML patients include the inhibition of phosphatidylinositol 3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) pathway, which is constitutively activated in leukemia cells and seems important for the regulation of cell proliferation, viability, and autophagy. In this study, we verified the effect of imatinib mesylate (IM), alone or in association with LY294002 (LY) (a specific PI3K protein tyrosine kinase inhibitor) or 4-amino-5-(4-methylphenyl)-7-(t-butyl)pyrazolo[3,4-d]-pyrimidine (PP1) (a Src tyrosine kinase inhibitor), on viability, intracellular calcium mobilization, apoptosis, and autophagy, in order to verify possible mechanisms of interaction. Our data demonstrated that PP1 and LY interact synergistically with IM by inducing apoptosis and autophagy in Bcr/Abl+ leukemia cells and this mechanism is related to the stress of the endoplasmic reticulum (ER). Our findings suggest a reasonable relationship between apoptotic and autophagic activity of tyrosine kinase inhibitors (TKIs) and the functionality of smooth ER Ca (2+)-ATPase and inositol triphosphate receptors, independently of intracellular calcium levels. Therapeutic strategies combining imatinib with PI3K and/or Src kinase inhibitors warrant further investigations in Bcr/Abl+ malignancies, particularly in the cases of imatinib mesylate-resistant disease.

Spin-dependent on-site electron correlations and localization in itinerant ferromagnets

Spin selectivity in angle-resolved Auger photoelectron coincidence spectroscopy (AR-APECS) is used to probe electron correlation in ferromagnetic thin films. In particular, exploiting the AR-APECS capability to discriminate Auger electron emission events characterized by valence hole pairs created either in the high or in the low total spin state, a strong correlation effect in the Fe M(2,3)VV Auger line shape (measured in coincidence with the Fe 3p photoelectrons) of Fe/Cu(001) thin films is detected and ascribed to interactions within the majority spin subband. Such an assignment follows from a close comparison of the experimental AR-APECS line shapes with the predictions of a model based on spin polarized density functional theory and the Cini-Sawatzky approach.

Value of diffusion-weighted images in differentiating mid-course responders to chemotherapy for osteosarcoma compared to the histological response: preliminary results

BACKGROUND

Preoperative diffusion-weighted MRI (DW-MRI) has been described as an efficient method to differentiate good and poor responders to chemotherapy in osteosarcoma patients. A DW-MRI performed earlier during treatment could be helpful in monitoring chemotherapy.

OBJECTIVE

To assess the accuracy of DW-MRI in evaluating response to chemotherapy in the treatment of osteosarcoma, more specifically at mid-course of treatment.

MATERIALS AND METHODS

This study was carried out on a prospective series of adolescents treated for long-bone osteosarcoma. MR examinations were performed at diagnosis (MRI-1), at mid-course of chemotherapy (MRI-2), and immediately before surgery (MRI-3). A DW sequence was performed using diffusion gradients of b0 and b900. The apparent diffusion coefficients (ADC1, ADC2, ADC3, respectively), their differentials (ADC2 - ADC1 and ADC3 - ADC1), and their variation (ADC2 - ADC1/ADC1 and ADC3 - ADC1/ADC1) were calculated for each of these three time points.

RESULTS

Fifteen patients were included. Patients with no increase in ADC showed a poor response to chemotherapy on their histology results. At mid-course, the three calculated values were significantly different between good and poor responders. ADC2 - ADC1 enabled us to detect, with 100% specificity, four out of seven of the poor responders. There was no significant difference in the values at MRI-3 between the two groups.

CONCLUSION

DW-MRI performed both at baseline and mid-course of neoadjuvant chemotherapy is an efficient method to predict further histological response of osteosarcoma. This method could be used as an early prognostic factor to monitor preoperative chemotherapy.

Peri-procedural tight glycemic control during early percutaneous coronary intervention is associated with a lower rate of in-stent restenosis in patients with acute ST-elevation myocardial infarction

OBJECTIVE

We examined the effects of peri-procedural intensive glycemic control (IGC) during early percutaneous coronary intervention (PCI) on restenosis rate in hyperglycemic patients with ST-segment elevation myocardial infarction (STEMI).

RESEARCH DESIGN AND METHODS

A total of 165 hyperglycemic patients (glucose ≥ 140 mg/dl) with first STEMI undergoing PCI were studied. Patients were randomized to IGC for almost 24 h after PCI (n = 82; glucose, 80-140 mg/dl) followed by multidose sc insulin during the hospital stay or conventional glycemic control (CGC; n = 83; glucose, 180-200 mg/dl) followed by conventional therapy. Coronary angiography was performed at study entry and at 6-month follow-up. Blood samples for glycemia, hemoglobin A1c, inflammatory markers (C-reactive protein and TNF-α), monocyte chemoattractant-protein-1, and oxidative stress (nitrotyrosine) were collected immediately before and 24 h, 30 and 180 d after PCI.

RESULTS

After insulin infusion, mean plasma glucose during the peri-procedural period was greater in the CGC group than in the IGC group (CGC, 191 ± 15 mg/dl; IGC, 145 ± 35 mg/dl; P < 0.001). After the insulin infusion period, the levels of markers of oxidative stress (nitrotyrosine), inflammation (C-reactive protein, TNF-α), and monocyte chemoattractant-protein-1 were significantly higher in CGC patients compared with IGC patients. Moreover, ICG during PCI reduces restenosis by half (48 and 24%) at 6 months. During follow-up, there was no difference in mortality rates, glucose, inflammatory and oxidative stress markers among the groups. In-stent restenosis was positively associated with mean plasma glucose levels as well as oxidative stress and inflammatory markers during the insulin infusion period.

CONCLUSIONS

In hyperglycemic patients with STEMI, optimal peri-procedural glycemic control by reducing oxidative stress and inflammation may improve the outcome after PCI.

Insight on hole-hole interaction and magnetic order from dichroic auger-photoelectron coincidence spectra

The absence of sharp structures in the Auger line shapes of partially filled bands has severely limited the use of electron spectroscopy in magnetic crystals and other correlated materials. By a novel interplay of experimental and theoretical techniques we achieve a combined understanding of the photoelectron, Auger, and Auger-photoelectron coincidence spectra (APECS) of the antiferromagnetic CoO. A recently discovered dichroic effect in angle resolved (DEAR) APECS reveals a complex pattern in the Auger line shape, which is here explained in detail, labeling the final states by their total spin. Since the dichroic effect exists in the antiferromagnetic state but vanishes at the Néel temperature, the DEAR-APECS technique detects the phase transition from its local effects, thus providing a unique tool to observe and understand magnetic correlations where the usual methods are not applicable.

The attenuation length of low energy electrons in Yb

Photoelectron emission spectra in a photon energy range between 7.5 and 21 eV are measured for in situ grown polycrystalline Yb films. By comparing bulk and surface core level shifted 4f components we give an estimation of the effective attenuation length (EAL) for low energy (6-20 eV) electrons in Yb, establishing a moderate increase of the EAL upon electron energy decrease. The experimental EAL data are found to be a factor of four smaller than those predicted from the so-called 'universal curve'.

Farnesyl transferase inhibitors induce neuroprotection by inhibiting Ha-Ras signalling pathway

In previous studies we found that the GTPase p21 Harvey-Ras (Ha-Ras) stimulates the production of reactive oxygen species and induces apoptosis by oxidative stress; this effect was reversed by farnesyl transferase inhibitors (FTIs). In this study we investigated whether FTIs reduce rat brain damage induced by an excitotoxic stimulus, and the signalling pathway(s) underlying the neuroprotection by FTIs. In brain tissue, protein levels of Ha-Ras and farnesylation inhibition were assayed by Western blot, and superoxide production was measured by hydroethidine. The excitotoxic lesion was induced by intrastriatal injection of N-methyl-d-aspartate (NMDA). The survival of mouse neuronal cortical cells was assessed by 3-(4,5 dimethylthialzol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). In brain tissue, NMDA increased the protein levels of Ha-Ras, FTIs caused the accumulation of non-prenylated inactive Ras in the cytosolic fraction, and significantly reduced superoxide production and necrotic volume after excitotoxicity. FTIs increased the viability of mouse neuronal cortical cells following oxidative stress. In conclusion, FTIs inhibited Ha-Ras, decreased oxidative stress and reduced necrotic volume by partly acting on neuronal cells. Thus, Ha-Ras inhibition plays a role in the pathology of neuroprotection, suggesting a potential role of FTIs in the treatment of cerebrovascular diseases.

2,7-Bis-(4-amidinobenzylidene)-cycloheptan-1-one dihydrochloride, tPA stop, prevents tPA-enhanced excitotoxicity both in vitro and in vivo

Tissue-type plasminogen activator (tPA) is available for the treatment of thromboembolic stroke in humans. However, adverse effects of tPA have been observed in animal models of ischemic brain injuries. In the present study, we have used a synthetic tPA inhibitor, named 2,7-bis-(4-amidino-benzylidene)-cycloheptan-1-one dihydrochloride (tPA stop), to investigate the role of endogenous tPA in the cerebral parenchyma. In mouse cortical cell cultures, we observed that although tPA stop reduced N-methyl-D-aspartic acid (NMDA)-mediated excitotoxic neuronal death, it failed to modulate alpha-amino-2,3-dihydro-5-methyl-3-oxo-4-isoxazole propanoic acid or kainate-mediated necrosis. In addition, we found that tPA stop could prevent the deleterious effects of both endogenous and exogenous tPA during NMDA exposure. At the functional level, tPA stop was found to prevent tPA-dependent potentiation of NMDA receptor-evoked calcium influx. The relevance of those findings was strengthened by the observation of a massive reduction of NMDA-induced excitotoxic lesion in rats when tPA stop was co-injected. Altogether, these data demonstrate that the blockade of the endogenous proteolytic activity of tPA in the cerebral parenchyma could be a powerful neuroprotective strategy raised against brain pathologies associated with excitotoxicity.

Reconstituted High-Density Lipoprotein Exhibits Neuroprotection in Two Rat Models of Stroke

BACKGROUND

Reconstituted high-density lipoprotein (rHDL) is prepared from apolipoprotein A-I, isolated from human plasma, and soybean-derived phosphatidylcholine and exhibits biochemical and functional characteristics similar to endogenous nascent high-density lipoprotein (HDL). This study tested the hypothesis that pretreatment with rHDL may reduce neuronal damage in 2 experimental rat models of stroke.

METHODS

In the first model, an excitotoxic lesion was induced by unilateral injection of N-methyl-D-aspartate (NMDA) in the right striatum (excitotoxic lesion model). In the second model, temporary occlusion of the middle cerebral artery (MCA) was attained by inserting a nylon thread through the carotid artery and blood flow was restored 30 min later (MCAo model). In both models, either rHDL (120 mg/kg) or saline (control) were infused over 4 h, starting 2 h before the injection of NMDA or the induction of ischemia, respectively. 24 h after the interventions, the rats were sacrificed and the brains removed for histochemical preparation. The necrotic area was delimited using an image analysis system. In addition, the levels of reactive oxygen species (ROS) in human endothelial (ECV 304) and neuroblastoma (SK-N-BE) cell lines were measured fluorometrically as 2',7'-dichlorofluorescein fluorescence in the presence and absence of rHDL and under basal and stress-induced conditions.

RESULTS

In the excitotoxic lesion and MCAo models, pretreatment with rHDL significantly reduced the brain necrotic area by 61 and 76%, respectively (p < 0.01). Overnight incubation of ECV 304 and SK-N-BE cells with 0.5 mg/ml rHDL decreased basal and stress-induced ROS levels by 73 and 72% (ECV 304) and by 76 and 43% (SK-N-BE), respectively (p < 0.01).

CONCLUSION

These results suggest that rHDL reduces neuronal damage after onset of ischemic stroke, possibly by involving an anti-oxidative mechanism. Thus, rHDL may be a powerful neuroprotective tool for the treatment of cerebrovascular diseases.

Hydrocortisone has a protective effect on CyclosporinA-induced cardiotoxicity

CyclosporinA (CsA) is an immunosuppressive drug which induces severe adverse effects such as cardiotoxicity and nephrotoxicity. In several therapeutic protocols CsA is used in association with corticosteroids to obtain better therapeutic results. Recently, our studies showed that CsA increases blood pressure while inhibit Nitric Oxide (NO) production in vivo. In this study we evaluated in rat cardiomyocytes the effects of CsA, used alone or in association with Hydrocortisone (HY), on intracellular calcium concentration, NO production and lipid peroxidation (MDA level). Our results demonstrated that CsA increased intracellular calcium and such effect was dose-dependent. HY used alone, slightly decreased intracellular calcium, while dramatically reduced CsA-induced calcium fluxes. CsA (3.2 microM) increased lipid peroxidation and this effect was blunted by HY. Both CsA and HY inhibited NO production in rat cardiomyocytes acting on this pathway synergically. Our results demonstrated that in rat cardiomyocytes, CsA toxicity is due to a calcium overload, which in turn induce lipid peroxidation and determines oxidative stress-induced cell injury. Treatment with HY effectively inhibits CsA-induced toxicity, decreasing lipid peroxidation as well as calcium intracellular concentration. Our findings seem to suggest that glucocorticoids may be effective in reducing CsA-induced cardiotoxicity at concentrations which are consistent with current therapeutic doses.

Protection of human endothelial cells from oxidative stress: role of Ras-ERK1/2 signaling

BACKGROUND

Reactive oxygen species play a critical role in inducing apoptosis. The small GTPase p21 Ras and the ERK1/2 MAPK have been proposed as key regulators of the signaling cascade triggered by oxidative stress (H2O2). Harvey-Ras (Ha-Ras) and Kirsten-Ras (Ki-Ras) isoforms are so far functionally indistinguishable, because they activate the same downstream effectors, including ERK1/2. Moreover, ERK1/2 signaling has been involved in both protection and induction of apoptosis.

METHODS AND RESULTS

Human umbilical vein endothelial cells (HUVECs) were subjected to H2O2, and apoptosis was detected by fluorescence-activated cell sorting analysis, fluorescence microscopy, and caspase-3 activation. Transfection of Ha-Ras and Ki-Ras genes in HUVECs was performed to evaluate the response to H2O2. We have found that, whereas Ha-Ras decreases tolerance to oxidative stress, Ki-Ras has a potent antiapoptotic activity. Both effects are mediated by ERK1/2. Tolerance to H2O2 is encoded by a unique stretch of lysines at the COOH terminus of the Ki-Ras, lacking in Ha-Ras, and it is relatively independent of the farnesylated anchor. Inhibition of p21 Ras signaling by farnesylation inhibitors increased the resistance to apoptosis in Ha-Ras-expressing cells.

CONCLUSIONS

These findings explain the opposite effects of ERK1/2 stimulation on apoptosis found in different cell types and suggest that local activation of ERK1/2 signaling may account for the opposing response to oxidative stress by Ha-Ras or Ki-Ras-expressing cells. Modulation of cell reactivity to oxidative stress by p21 Ras points to the specific and predictive effects of Ras inhibitors in vivo as potential therapeutic drugs in disorders produced by increase of reactive oxygen species inside the cells.

Plasma folate, vitamin B(12), and total homocysteine and homozygosity for the C677T mutation of the 5,10-methylene tetrahydrofolate reductase gene in patients with Alzheimer's dementia. A case-control study

BACKGROUND

Elevated total plasma homocysteine (tHcy) levels are considered a risk factor for cerebrovascular disease and may also play an important role in the pathogenesis of Alzheimer's disease (AD). High values of plasma tHcy and low levels of vitamin B(12) and folate are frequently present in AD patients. Moreover, the homozygous mutation (C677T) of the methylene tetrahydrofolate reductase (MTHFR) gene, related to a thermolabile type of the encoded enzyme, causes hyperhomocysteinemia by reducing the 5-methyltetrahydrofolate availability.

OBJECTIVE

The aim of the study was to investigate plasma levels of folate, vitamin B(12) and tHcy in patients with AD. These values were also related to the severity and the duration of the disease and to the possible role of the MTHFR genotype (C677T).

METHOD

Plasma tHcy levels, homozygosity for the C677T mutation of the MTHFR gene, and folate and vitamin B(12) plasma levels were evaluated in 74 patients with AD (45 men, 29 women, mean age 68 years) and in 74 healthy matched controls (42 men, 32 women, mean age 68 years).

RESULTS

AD patients had higher mean (+/- SD) plasma levels of tHcy (20.9 +/- 15 micromol/l compared to 11.8 +/- 5 micromol/l, p < 0.001) and lower mean plasma folate (5.7 +/- 2.1 ng/ml compared to 8.5 +/- 3.2 ng/ml, p < 0.001) and vitamin B(12) (491 +/- 144 pmol/l compared to 780 +/- 211 pmol/l, p < 0.001) concentrations. Homozygosity for the C677T mutation of the MTHFR gene had a similar prevalence among controls (18%) and AD patients (20%). Homozygous AD patients (n = 15) had higher plasma tHcy values than nonhomozygotes, in spite of similar mean plasma folate and vitamin B(12) levels. This difference in plasma tHcy levels was not observed in controls. Patients with levels of plasma tHcy above and of plasma folate below the normal limits were more frequent in the homozygous AD group. The duration of the disease correlated with plasma levels of tHcy (r = +0.832, p < 0.001), plasma folate (r = -0.580, p < 0.05), and vitamin B(12) (r = -0.460, p < 0.05). However, when all the data were corrected for age, serum creatinine levels, and duration of the disease, mean plasma tHcy, folate, and vitamin B(12) levels were not statistically different between controls and AD patients.

CONCLUSIONS

Our data suggest that rather than a risk factor for AD, hyperhomocysteinemia is related to its progression and increasing severity. This might be particularly relevant in homozygotes for the C677T mutation of the MTHFR gene and supports the possible need for continuous supplements in this setting.

A transforming growth factor-beta antagonist unmasks the neuroprotective role of this endogenous cytokine in excitotoxic and ischemic brain injury

Various studies describe increased concentrations of transforming growth factor-beta (TGF-beta) in brain tissue after acute brain injury. However, the role of endogenously produced TGF-beta after brain damage to the CNS remains to be clearly established. Here, the authors examine the influence of TGF-beta produced after an episode of cerebral ischemia by injecting a soluble TGF-beta type II receptor fused with the Fc region of a human immunoglobulin (TbetaRIIs-Fc). First, this molecular construct was characterized as a selective antagonist of TGF-beta. Then, the authors tested its ability to reverse the effect of TGF-beta1 on excitotoxic cell death in murine cortical cell cultures. The addition of 1 microg/mL of TbetaRIIs-Fc to the exposure medium antagonized the neuroprotective activity of TGF-beta1 in N-methyl-D-aspartate (NMDA)-induced excitotoxic cell death. These results are consistent with the hypothesis that TGF-beta1 exerts a negative modulatory action on NMDA receptor-mediated excitotoxicity. To determine the role of TGF-beta1 produced in response to brain damage, the authors used a model of an excitotoxic lesion induced by the intrastriatal injection of 75 nmol of NMDA in the presence of 1.5 microg of TbetaRIIs-Fc. The intrastriatal injection of NMDA was demonstrated to induce an early upregulation of the expression of TGF-beta1 mRNA. Furthermore, when added to the excitotoxin, TbetaRIIs-Fc increased (by 2.2-fold, P < 0.05) the lesion size. These observations were strengthened by the fact that an intracortical injection of TbetaRIIs-Fc in rats subjected to a 30-minute reversible cerebral focal ischemia aggravated the volume of infarction. In the group injected with the TGF-beta1 antagonist, a 3.5-fold increase was measured in the infarction size (43.3 +/- 9.5 versus 152.8 +/- 46.3 mm3; P < 0.05). In conclusion, by antagonizing the influence of TGF-beta in brain tissue subjected to excitotoxic or ischemic lesion, the authors markedly exacerbated the resulting extent of necrosis. These results suggest that, in response to such insults, brain tissue responds by the synthesis of a neuroprotective cytokine, TGF-beta1, which is involved in the limitation of the extent of the injury. The pharmacologic potentiation of this endogenous defensive mechanism might represent an alternative and novel strategy for the therapy of hypoxic-ischemic cerebral injury.

Alterations of cerebral blood flow and antiphospholipid antibodies in patients with systemic lupus erythematosus

Twenty-two patients with systemic lupus erythematosus and 13 healthy controls were included in a cerebral blood flow study and underwent brain-dedicated single-photon emission computed tomography using 99m technetium-d, l-hexamethylpropylene amine oxime together with a brain computed tomography scan. Plasma levels of antiphospholipid antibodies (lupus anticoagulant and anticardiolipin IgM and IgG antibodies) were also determined. Brain computed tomography showed signs of focal cerebral ischemia in 4 patients (18%), whereas cerebral blood flow by single-photon emission computed tomography was abnormal in 13 of 22 patients (59%), who showed bilateral or monolateral hypoperfusion in the temporo-parietal regions. Patients with abnormal cerebral blood flow had a longer duration of disease than those with normal blood flow (8.9 +/- 1.9 years vs. 5.3 +/- 1.5 years, P < 0.05). Plasma antiphospholipid antibodies were present in 15 patients (68%), but the prevalence was similar in those with normal (6/9, 66%), or abnormal (9/13, 69%) cerebral blood flow. No statistically significant difference in lupus anticoagulant or anticardiolipin antibodies was observed between patients with and without cerebral blood flow abnormalities. Our study shows that patients with systemic lupus erythematosus frequently have cerebral blood flow abnormalities, which could precede those observed by computed tomography. Plasma lupus anticoagulant and anticardiolipin titers were not correlated with normal cerebral blood flow.

Prevalence of peripheral arterial disease in an elderly rural population of southern Italy

Blood pressure was measured at the posterior tibial artery by Doppler ultrasonography in 440 elderly subjects (205 men and 235 women) living in a rural community of Southern Italy, together with the evaluation of traditional risk factors for cardiovascular disease. An ankle/arm systolic pressure ratio below 0.90 was considered as a definite pathological sign of peripheral arterial disease (PAD). About 10% of both men and women had a value below 0.90. Elderly subjects with PAD had higher serum triglyceride levels and a higher ratio between the cholesterol content in atherogenic (VLDL + LDL) versus non-atherogenic (HDL) lipoproteins than subjects free of PAD. The mean blood pressure was also higher in patients with PAD. The prevalence of PAD was much lower than what we have observed in institutionalized old subjects in Southern Italy.

Decreased low-density lipoprotein oxidation after repeated selective apheresis in homozygous familial hypercholesterolemia

Familial hypercholesterolemia was the first genetic disorder recognized to cause myocardial infarction. Patients with homozygous familial hypercholesterolemia have rapidly progressive coronary atherosclerosis with angina pectoris, myocardial infarction, or sudden death at a young age. Selective apheresis on dextran sulfate cellulose columns reduces mortality and may induce regression of coronary lesions. These patients have both increased levels and prolonged circulation residence time of low-density lipoprotein (LDL), which is not removed by cellular receptor. LDL oxidation may play a pivotal role in atherogenesis. LDL undergoes oxidation before being taken up by macrophages and then transformed into arterial wall foam cells. The aim of this study was to investigate LDL oxidation in eight homozygous patients with familial hypercholesterolemia during repeated LDL apheresis. LDL lipid peroxidation, estimated by conjugated-diene absorbance at 234 nm, lipid peroxides, and malondialdehyde showed an increased resistance against oxidation after repeated LDL apheresis. This phenomenon was also observed in the oxidative indexes of protein moiety of LDL (apolipoprotein-B100 fragmentation, trinitrobenzenesulfonic acid reactivity, and electrophoresis agarose mobility). Similarly, cholesteryl esterification was decreased after LDL apheresis. Thus selective LDL apheresis not only decreases the pool of LDL, but it also induces changes that render LDL less susceptible to oxidation. This phenomenon might contribute to reduce coronary atherosclerosis and thus mortality of these particular patients.

Premature aging in Werner's syndrome spares the central nervous system

Werner's Syndrome is a rare genetic disease, characterized by premature aging of many tissues and organs. We studied the brain morphology and function in two patients with Werner's syndrome to assess the possible involvement of the central nervous system in this premature aging process. The two patients (brother and sister, respectively) were studied by magnetic resonance imaging (MRI) and angiography (MRA), single photon emission computed tomography (SPECT) with (99mTc)-d,l-hexamethyl propilene amine oxime (HMPAO), positron emission tomography (PET) with 2(18F)-Fluoro-2-deoxyglucose (FDG), electroencephalography (EEG), and electromyography (EMG). Some of these investigations were also repeated after 1 year. The results of all these studies were normal. The premature aging process in patients with Werner's syndrome, while affecting most tissues, seems to spare the central nervous system.

Oxidative structural modifications of low density lipoprotein in homozygous familial hypercholesterolemia

Patients with homozygous familial hypercholesterolemia (FH), as a result of the increased levels and prolonged residence time of low density lipoprotein (LDL) in plasma, have a strong tendency toward accumulation of LDL-cholesterol in the arterial wall, causing premature atherosclerosis. This phenomenon may enhance per se the physiological degradation of both protein and lipid component of LDL, which be more susceptible to oxidative damage induced by oxygen radicals. It is well known that LDL may undergo oxidative modification before being taken up by macrophages which are then transformed into foam cells. It has been suggested that platelet-activating factor (PAF) may play an important role in atherogenesis and PAF catabolism is known to be mediated by serum acetylhydrolase, an enzyme that is normally associated with LDL. Thus, the present study was designed to investigate the structural properties of LDL, including acetylhydrolase activity, in homozygous FH as compared to normolipidemic subjects before and after xanthine/xanthine oxidase-mediated oxidation. We studied 8 homozygous FH patients matched with 8 normolipidemic volunteers. Lipids of LDL fraction were extracted and verified by thin layer chromatography (TLC) analysis. Fatty acids were methylated and injected into a gas chromatograph/mass spectrometer. Vitamin E in LDL was determined by high performance liquid chromatography (HPLC). As an index of susceptibility of LDL to oxidative modifications, the formation of lipid-conjugated dienes was continuously monitored at 234 nm. Lipid peroxidation was also evaluated from the amount of both lipid peroxides (LPO) and malonyldialdehyde (MDA) content. Apolipoprotein (apo) B-100 on LDL was carried on polyacrylamide and agarose gel electrophoresis. In the homozygous FH patients, the relative content of cholesteryl ester was slightly increased. Interestingly, the relative amount of arachidonic acid (20:4) was constantly increased in each lipid fraction in homozygous FH patients. The amount of vitamin E was not significantly different in the patient group from that in the control group. However, LDL from patients carried lower levels of vitamin E (nmol/mg LDL) than controls (2.7 +/- 0.4 vs. 2.9 +/- 0.3 P = NS). The results shows that lag time (min) was decreased (82 +/- 19 vs. 111 +/- 21; P < 0.05) and the maximal rate of diene production and total diene production was increased in homozygous FH patients. Mean levels of MDA were similar in both groups before oxidation, but levels after initiation of oxidation were significantly higher in the patient group. In contrast, mean levels of LPO were already higher in patients before oxidation (58 vs. 27 nmol/mg of protein; P < 0.05), and after initiation of oxidation were also significantly higher at each time points. When oxidized LDL was run on a polyacrylamide gel, an extensive apo B-100 fragmentation replaced by lower molecular mass fragments ranging from 45,000 to 205,000 m.wt., was observed only in LDL from homozygotes. Relative LDL agarose gel mobility shows that LDL from patients migrated higher than LDL of controls. Finally acetylhydrolase activity associated with LDL in patients was significantly reduced as compared to controls. Thus, in homozygous FH patients, LDL appeared more susceptible to oxidation in vitro; the indices for LDL oxidizability were all significantly different from those of controls. This phenomenon might be due to prolonged residence time of LDL in these patients, as suggested from high basal LPO levels and lower vitamin E levels carried by LDL. This hypothesis may explain together with the high content of arachidonic acid, the enhanced susceptibility of LDL from homozygous FH patients to oxidative damage.

Effect of adenosine on cerebral blood flow as evaluated by single-photon emission computed tomography in normal subjects and in patients with occlusive carotid disease. A comparison with acetazolamide

BACKGROUND AND PURPOSE

Acetazolamide is commonly used with single-photon CT to assess the cerebrovascular reserve in patients with internal carotid artery stenosis or occlusion. In this study we wanted to evaluate the effects of adenosine, a well-known vasodilatatory compound with a short biological half-life, on brain circulation in humans and compare the results with those of acetazolamide.

METHODS

Acetazolamide (1 g) and adenosine (140 micrograms/kg per minute) were injected intravenously on different days in 6 normal subjects and 6 patients: 4 with unilateral stenosis, 1 with bilateral stenosis, and 1 with complete occlusion of the internal carotid artery. Changes in regional cerebral blood flow relative to that of the cerebellum (cortico/cerebellar ratios) from resting conditions were evaluated by 99mTc-hexamethylpropyleneamine oxime and single-photon emission CT.

RESULTS

The measured blood flow ratios increased significantly in the normal group 20 minutes after acetazolamide injection in several cortical and subcortical regions, as well as at the 4th minute of a 6-minute adenosine infusion. Regional cerebral blood flow ratio values were higher after adenosine than after acetazolamide in both cortical (frontal and parietal) and subcortical (thalamus and basal ganglia) regions. In 4 of the 6 patients the side-to-side asymmetry increased from the basal resting condition after the injection of acetazolamide and even more so after the injection of adenosine.

CONCLUSIONS

Adenosine infusion causes vasodilation of cerebral arteries and can be used for the investigation of cerebrovascular perfusion capacity in patients with carotid occlusive disease. One advantage in the use of adenosine over acetazolamide is the possibility of interrupting the test with reversal of clinical symptoms or patient discomfort within a few minutes.